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<title>Using as: MIPS FP ABI Selection</title>

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<a name="MIPS-FP-ABI-Selection"></a>
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Next: <a href="MIPS-FP-ABI-Compatibility.html#MIPS-FP-ABI-Compatibility" accesskey="n" rel="next">MIPS FP ABI Compatibility</a>, Previous: <a href="MIPS-FP-ABI-Variants.html#MIPS-FP-ABI-Variants" accesskey="p" rel="prev">MIPS FP ABI Variants</a>, Up: <a href="MIPS-FP-ABIs.html#MIPS-FP-ABIs" accesskey="u" rel="up">MIPS FP ABIs</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
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<a name="Automatic-selection-of-FP-ABI"></a>
<h4 class="subsubsection">9.27.9.3 Automatic selection of FP ABI</h4>
<a name="index-_002emodule-fp_003dnn-directive_002c-MIPS"></a>
<p>In order to simplify and add safety to the process of selecting the
correct floating-point ABI, the assembler will automatically infer the
correct <code>.gnu_attribute 4, <var>n</var></code> directive based on command line
options and <code>.module</code> overrides.  Where an explicit
<code>.gnu_attribute 4, <var>n</var></code> directive has been seen then a warning
will be raised if it does not match an inferred setting.
</p>
<p>The floating-point ABI is inferred as follows.  If &lsquo;<samp>-msoft-float</samp>&rsquo;
has been used the module will be marked as soft-float.  If
&lsquo;<samp>-msingle-float</samp>&rsquo; has been used then the module will be marked as
single-precision.  The remaining ABIs are then selected based
on the FP register width.  Double-precision is selected if the width
of GP and FP registers match and the special double-precision variants
for 32-bit ABIs are then selected depending on &lsquo;<samp>-mfpxx</samp>&rsquo;,
&lsquo;<samp>-mfp64</samp>&rsquo; and &lsquo;<samp>-mno-odd-spreg</samp>&rsquo;.
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